Add support for workspace.dependencies

[Christiaan676]

Is your feature request related to a problem? Please describe. With the Rust 1.64 release support was added for workspace dependencies. The plugin will correctly detect the dependencies in the workspace Cargo.toml, but the <dependencie>.workspace = true in the projects in the workspace will result in three red exclamation marks.

Describe the solution you'd like Don't show the red exclamation marks in the project dependencies when the dependency exists in the workspace.